I have a 2001 expedition with the 5.4 and 2wd if that makes any difference. 170k miles. When accelerating in the 1000-1800rpm range my Expedition shakes and the engine stumbles until around 2000 rpm that its fine after 2000 rpm. If rpms drop below 2000 rpm than the truck starts doing it all over again. I replaced the fuel filter yesterday and one coil about two months ago and the boot and spring for another coil today. The truck started doing this about a week ago. I have noticed that there is coolant on the outside of the spark plug boots on the number 1 and number 4 cylinders, I have also replaced the head gaskets, intake manifold gaskets, throttle body gasket, new coolant, oil, etc. The previous owner told me that the fuel pump was recently changed but I do not know if that's true. I need this Expedition as its my only vehicle other than my wife's and she needs hers all the time for school and work. Please any help would be greatly appreciated. What are the chances that it could just be the coils need to be changed? Maybe fuel pump?

 

Ok...

You said you changed the intake gaskets. No biggie, but did you inspect the crap plastic intake manifold? They fail right there by #1. That coolant crossover tube cracks and causes similar problems. May need to rent coolant psi tester and verify. If that intake is that old, chances are, that's your problem. I had exact same problem.

 

I forgot to mention the truck has 170k on it so now that i think about it that could very well be the problem. ill take a look at it tomorrow. Thank you. I am not to familiar with these engines so that being said is the coolant crossover tube the one that sticks out from the front right of the intake (where heater hose hooks up) or is internal or underneath the intake manifold. Sorry for my ignorance on this topic.

 

nevermind i figured out the coolant cross over. its the metal peice under the intake in front

 

Does the coolant crossover leak externally or internally? i can only see coolant on the boots. I cannot see a leak anywhere on outside of manifold or top of cylinder head

 

Externally. It runs under the manifold to the back passenger side. If it was leaking, you'd see antifreeze under the manifold but on top of the engine and there's a rare chance it could work into a plug hole but the COP's seal pretty good at the top.

It's probably the intake manifold or gasket as discussed.

 

Mine leaked externally, ran down the valve covers, filled the plug wells up on 1, 2, 3. Also filled the center of engine under manifold.

 

Would the all aluminum manifold from a 99 work on the 01? If both have the 5.4

 

I did some Google'ing when I did mine. Research showed it should it should, but it also had different coolant hose connections. I read that some had replaced them with the aluminum type from the '99's.

Also, either in 2003 or beginning of 2004, Ford worked with DuPont on a new "plastic formula" that would prevent this from happening in later models.

I choose Dorman for the replacement,due to cost. If cost wasn't an issue, I would have chosen Motorcraft. Also, the Dorman intake has the intake gaskets molded directly into it.

 

Would the intake be able to leak onto the coil boots without a leak being visible frim the outside?

 

I had the same symptom with same model/year but much less mileage. Tech read diag code to find the failing coil.

 

I have no codes stored, pending, and no check engine light. battery was recently disconnected though but i have driven it and no codes came up or any pending

 

Thank you to all who answered and offered help. I replaced the manifold from a truck with lower mileage and my Expedition is now back to normal. Truck runs great and no issues so far.

 

Glad to hear its running well again.

 

good news！